small bento box dunno what to fit

That's what my first bento looks like. It's smaller than I expected so I'm not sure I can fit the stuff in that I wanted to cook. Any advice on organizing or things that specifically fit in here? I'm not quite sure what to do. It is smaller than I'd expected but it's my first bento purchase so I'm not sure whether I'm underestimating how much I could put into it.